http://jhuapl.edu/newscenter/pressreleases/2017/171019.asp
Narrow dense rings of comets are coming together to form planets on the outskirts of at least three distant solar systems, astronomers have found in data from a pair of NASA telescopes.
Estimating the mass of these rings from the amount of light they reflect shows that each of these developing planets is at least the size of a few Earths, according to Carey Lisse, a planetary scientist at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland.
Over the past few decades, using powerful NASA observatories such as the Infrared Telescope Facility in Hawaii and the Spitzer Space Telescope, scientists have found a number of young debris disk systems with thin but bright outer rings composed of comet-like bodies at 75 to 200 astronomical units from their parent stars — about two to seven times the distance of Pluto from our own Sun. The composition of the material in these rings varies from ice-rich (seen in the Fomalhaut and HD 32297 systems) to ice-depleted but carbon rich (the HR 4796A system).
[...] In Fomalhaut and HD 32297, researchers expect that millions of comets are contributing to form the cores of ice giant planets like Uranus and Neptune — although without the thick atmospheres enveloping the cores of Uranus and Neptune, since the primordial gas disks that would form such atmospheres are gone. In HR 4796A, with its warmer dust ring, even the ices normally found in the rings' comets evaporated over the last million years or so, leaving behind core building blocks that are rich only in leftover carbon and rocky materials. "These systems appear to be building planets we don't see in our solar system — large multi-Earth mass ones with variable amounts of ice, rock and refractory organics," Lisse said. "This is very much like the predicted recipe for the super-Earths seen in abundance in the Kepler planet survey."
The supposed exoplanets could also be called "massive solid planets" or "mega-Earths".
Infrared Spectroscopy of HR 4796A's Bright Outer Cometary Ring + Tenuous Inner Hot Dust Cloud
(Score: -1, Troll) by Anonymous Coward on Wednesday October 25 2017, @02:25AM (2 children)
In billions of years, one of these places will be home to some civilization.
You think they'll be cuttings bits of flesh from their children's sexual organs, too?
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @02:31AM (1 child)
No, I don't.
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @02:37AM
Why would a real civilization even use sex? Why would they have sexual organs? Why do you backward earthlings presume that a real civilization would resemble your own lack of culture?
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @02:41AM (8 children)
Are these planets, or just a bunch of comets accreted?
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @02:50AM
Yes.
(Score: 2) by takyon on Wednesday October 25 2017, @02:50AM
Looks like yet another job for JWST.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by c0lo on Wednesday October 25 2017, @02:50AM (5 children)
No.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 1, Redundant) by c0lo on Wednesday October 25 2017, @02:52AM (4 children)
No, they aren't planets. Latest planet definition involve "cleaned its orbit of debris" - since there is still a ring, they aren't planets by this definition.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @08:04AM (3 children)
Please understand what IAU actually means when they say "clearing the neighbourhood" [wikipedia.org] first. In short, it means that the body has become gravitationally dominant in its orbit, i.e. there are no other objects of comparable size in its orbital zone other than its satellites or other objects gravitationally bound to it. A ring system is gravitationally bound to its planet, so it doesn't count.
(Score: 2) by c0lo on Wednesday October 25 2017, @09:56AM (2 children)
The ring system mentioned in TFS (at least) is surrounding the star (not the planet)
Details on Wikipedia [wikipedia.org] page.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 0) by Anonymous Coward on Wednesday October 25 2017, @10:50AM (1 child)
(Score: 2) by c0lo on Wednesday October 25 2017, @11:51AM
So, no, they are not planets.
Wiki page indicate they may not be even protoplanets, just a pile of rubble still orbiting together but not yet gravitationaly bound in a single body.
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 3, Interesting) by Arik on Wednesday October 25 2017, @02:53AM (7 children)
In retrospect, I rather suspect a different sort of adaption instead. More like a koala bear than a grizzly, perhaps. The inverse square law rather argues against the massive form.
If laughter is the best medicine, who are the best doctors?
(Score: 2, Funny) by Anonymous Coward on Wednesday October 25 2017, @02:59AM
A stronger gravity favors Thylarctos plummetus
(Score: 3, Interesting) by takyon on Wednesday October 25 2017, @03:01AM (5 children)
There are super-Earths with a surface gravity of far less than 2g despite having several times Earth's mass:
https://www.psychologytoday.com/blog/world-wide-mind/201211/do-super-earths-have-too-much-gravity-us [psychologytoday.com]
If these comet ring planets are low in ice, they could have a higher density and surface gravity than typical super-Earths. Although they are probably too cold for life.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by Arik on Wednesday October 25 2017, @03:10AM (4 children)
"Although they are probably too cold for life."
On the surface perhaps, but if they have molten cores and vulcanism then there should be plenty of opportunities for life beneath.
If laughter is the best medicine, who are the best doctors?
(Score: 3, Interesting) by Fluffeh on Wednesday October 25 2017, @03:49AM (3 children)
Actually, although this sort of volcanic activity can lead to simple life - it is unlikely to create more complex life as the energy density (availability) is not high enough.
Here's an interesting paper if you want to do some extra reading: http://www.pnas.org/content/111/35/12628.full [pnas.org]
Here's a section that talks about energy density:
(Score: 2) by Arik on Wednesday October 25 2017, @04:07AM (2 children)
If laughter is the best medicine, who are the best doctors?
(Score: 2) by Fluffeh on Wednesday October 25 2017, @04:43AM (1 child)
Certain parts of the body require a LOT of energy to function. Our brains, as small as they are compared to the rest of the body account for about 20% of the total energy we use. Additionally, while it can be theorized that with a smaller amount of energy to use, evolution creates life that uses it sparingly (such as animals that move slower for example - like the Sloth) - but it just makes it less likely.
I'm not saying it is impossible - if the universe is infinite, then it's certainly happening somewhere, just the chances of it happening in a particular place is small.
The other thing you need to think about from a biological point of view, is that there are vast amounts of various extremophiles here on earth - all manner of things that lives in amazing environments from ultra saline water to radioactive bars in reactors - but these have ADAPTED from life that already existed. If you had a planet where the ONLY environment was plutonium bars in water, the those things just wouldn't pop into existence one day. You have to have a certain set of conditions for the super primitive life to get a start, then you can wind up the difficulty levels so to speak.
(Score: 2) by Arik on Wednesday October 25 2017, @05:41AM
Anyway my point wasn't about the likelihood but about the shape it might take, and I do like that sloth idea.
Perhaps small sloth-like beings, with dense muscles and opposable thumbs, for climbing in lava vents rather than trees so I imagine thickly padded palms. Perhaps with heads of Organian proportions.
If laughter is the best medicine, who are the best doctors?